During the last 25 years, the role of gynecologic laparoscopy has evolved from a limited surgical procedure used only for diagnosis and tubal ligation, to a major surgical tool used to treat a multitude of gynecologic indications. Laparoscopy has become one of the most common surgical procedures performed by gynecologists.
For many procedures, such as removal of ectopic pregnancies and treatment of endometriosis, the cost-to-benefit ratio is well established, particularly in terms of expense and safety. For other procedures, including laparoscopically assisted hysterectomy and staging of gynecologic cancers, the ultimate utility of this approach remains to be clearly defined.
History of the Procedure: Laparoscopy was first performed in animals in the early 1900s, and the Swedish surgeon Jacobaeus coined the term laparoscopy (laparothorakoskopie) in 1901. It was not until the early 1960s, however, that better techniques were developed and laparoscopy was accepted as a safe and valuable procedure. Initially, laparoscopy was performed almost exclusively for diagnosis and sterilization. By the late 1970s, the role of laparoscopy had expanded to include lysis of adhesions and treatment of endometriosis. Technology and equipment have now advanced to include the use of laparoscopy in hysterectomies, incontinence procedures, and operations for gynecological malignancies.
Problem: Laparoscopy is a unique surgical approach that shares characteristics of both minor and major surgery. To patients, laparoscopic procedures often are considered to be minor surgery because of small incisions, a relatively small amount of postoperative pain, and short convalescent period. If a laparoscopic procedure involves minimal intra-abdominal surgery (eg, diagnostic laparoscopy, tubal fulguration), both postoperative discomfort and risk of complications may more closely resemble a minor procedure than a major procedure.
At its essence, laparoscopy remains an intra-abdominal procedure. It therefore shares all intraoperative and postoperative risks of laparotomy, including infection and injury to adjacent intra-abdominal structures. When major intra-abdominal procedures are performed laparoscopically (eg, hysterectomy), the resultant postoperative pain and morbidity are still significant, but they always are less significant than similar major surgery performed by laparotomy since a large abdominal incision is unnecessary.
Laparoscopic procedures have unique risks, which are related to methods used for placement of abdominal wall ports and to the pneumoperitoneum required for laparoscopy. These risks include injury to bowel, bladder, or major blood vessels, and intravascular insufflation. In addition, increased intra-abdominal pressures associated with laparoscopy increase anesthesia-related risks such as aspiration and increased difficulty ventilating the patient. Although risk of blood loss is relatively low for most procedures, potentially massive blood loss may occur and is complicated by the fact that control of blood loss may be delayed by the time taken to perform an emergency laparotomy.
Frequency: Laparoscopy is one of the most common surgical procedures performed in the United States today. Approximately half of the 700,000 bilateral tubal sterilizations done annually in the United States are performed laparoscopically. In addition to diagnostic laparoscopy, operative endoscopy is used to perform common procedures including removal of ectopic pregnancies, treatment of endometriosis, and lysis of pelvic adhesions. Many of the 650,000 hysterectomies performed annually in the United States are now being done with laparoscopic aid. Although the ideal role of laparoscopy in gynecologic surgery is still being defined, use of this approach is likely to become more common in years to come.
Frequently, the physician needs to assess the pelvis for acute or chronic pain, ectopic pregnancy, endometriosis, adnexal torsion, or other pelvic pathology. Determination of tubal patency also may be an issue. Usually, the camera lens is placed infraumbilically and a second port is placed suprapubically to probe systematically and observe pelvic organs. If needed, a biopsy can be obtained to diagnose endometriosis or a malignancy. If tubal patency is a concern, use of a uterine manipulator with a cannula allows a dilute dye to be injected transcervically (chromopertubation).
Trocar placement is similar to diagnostic laparoscopy. Bipolar electrosurgery, clips, or silastic bands may be used to occlude the tubes at the mid-isthmic portion, approximately 3 cm from the cornua. Bipolar surgery desiccates the tube with 3 adjacent passes to occlude approximately 2 cm of tube. The auditory tone now available to verify total resistance has improved the efficacy of bipolar cautery. Pregnancy rates vary by patient age, ranging from 1-3% after 10 years.
Lysis of adhesion
Adhesions may form due to prior infection, such as a ruptured appendix or pelvic inflammatory disease (PID), endometriosis, or previous surgery. Adhesions may contribute to infertility or chronic pelvic pain. Adhesions may be lysed by blunt or sharp dissection. Aquadissection may aid in the development of planes prior to lysing. Any of the power instruments may be utilized for cutting and coagulation. Unipolar electrosurgery, such as the fine unipolar needle, should be limited to adhesions 1-2 cm from the ureter and bowel due to the unpredictable nature of current arcing. Other power techniques may be safer choices for adhesiolysis near the bowel.
Adhesions may reform after lysis, although this can be reduced with good hemostasis. Surgeons frequently utilize intraperitoneal anti-inflammatory solutions of steroids and dextran-70, but these have not proven beneficial in controlled trials. Although proven to decrease adhesions in clinical trials, barrier methods have been disappointing in terms of improving pain relief or future fertility.
Fulguration of endometriosis
Endometriotic lesions may be resected or ablated using any of the power instruments. This has been shown to improve fertility and decrease pelvic pain.
Treatment of ectopic pregnancy
Laparoscopy is the surgery of choice for most ectopic pregnancies. A salpingostomy or salpingectomy may be used to remove the embryo and gestational sac. Auxiliary instruments, such as pre-tied loops or stapling devices, may be particularly well suited for the salpingectomy, although any of the power instruments work equally well.
If an ovarian simple cyst sized 6 cm or larger persists for 2 or more cycles in a premenopausal, nonpregnant female, a cystectomy is indicated. This can be done by laparoscopy or laparotomy depending upon cyst size and degree of suspicion for malignancy.
The cyst can be removed by a number of techniques. If the cyst is complex, rule out malignancy by looking for signs of ascites, excrescences on the ovary, or implantations on the peritoneal, liver, or diaphragmatic surfaces. If malignancy is not apparent, carefully dissect the cyst, making an effort to remove the cyst intact. A bag may be used to transfer the cyst out of the peritoneal cavity through a 10-mm port, draining the cyst prior to removal of the bag. If there is any doubt, the cyst wall should be sent for frozen section to confirm a benign cyst. If malignancy is found, a laparotomy should be performed. Permanent section and pathological diagnosis are performed on all cysts. Ovarian cysts with septa, internal echoes, or solid tumors are not good candidates for laparoscopy unless a benign cystic teratoma is strongly suspected.
If the cyst ruptures during removal, liberally rinse the peritoneal cavity with lactated Ringer's solution. A dermoid cyst is particularly concerning due to contamination of the peritoneal cavity with sebaceous material, causing a chemical peritonitis. Fear of seeding the cavity with a malignant tumor always has been present, although recent data suggest that spilling does not alter prognosis if a staging laparotomy is carried out immediately. Postmenopausal cysts also may be removed by laparoscopy, although with the increased concern for malignancy, an oophorectomy and laparotomy may be more prudent. Physicians who perform a laparoscopy should be comfortable with staging by laparoscopy or laparotomy, and malignancy should be ruled out perioperatively.
As stated above, an oophorectomy may be more appropriate in postmenopausal women with a growing or persistent cyst. A tubal pregnancy or large hydrosalpinx with adhesions also may require ovary removal. The power instruments, pre-tied loops, or stapling devices may be used to occlude the infundibular ligament and safely remove the ovary. Because of ovary size, a retrieval bag is needed to remove the tissue. Options for removing the ovary from the peritoneal cavity include using a 12-mm port and removing the sleeve with the bag, or performing a minilaparotomy or colpotomy. If a colpotomy is performed, prophylactic antibiotics should be given.
Many women with a symptomatic fibroid uterus prefer myomectomy to hysterectomy in order to preserve fertility or the uterus. If the patient has a pedunculated fibroid, the stalk may be easily incised. For intramural fibroids, however, risk of bleeding increases. An injection of vasopressin into the uterus may help maintain hemostasis. The defect left by the fibroid must be sutured, which can be difficult by laparoscopy for the inexperienced. Barrier techniques may be used to decrease adhesion formation.
The fibroid may be removed by morcellation or colpotomy. Power morcellators are available to expedite the process. To date, laparoscopy has not proven better than laparotomy for treatment of menorrhagia or infertility. In addition, some concern exists that the risk of subsequent uterine rupture during pregnancy may be greater after myomectomy performed by laparoscopy than by laparotomy.
Initially, laparoscopy was performed prior to vaginal hysterectomy to restore normal anatomy. Currently, however, it often is used in a variety of ways, such as assessing feasibility of a vaginal hysterectomy (when suspecting adhesions, endometriosis, or large fibroid uterus) and performing some or all of the actual hysterectomy. The 3 basic laparoscopic approaches for hysterectomy are laparoscopic-assisted vaginal hysterectomy (LAVH), laparoscopic hysterectomy (LH), and laparoscopic supracervical hysterectomy (LSH). Although the basic techniques for each approach are fairly standardized, controversy exists over the risks, benefits, and most appropriate indications of each.
LAVH is the most commonly employed and technically straightforward of the 3 techniques. Using 3-4 ports, the peritoneal cavity is surveyed and lysis of adhesions is performed if necessary. The infundibular or utero-ovarian ligaments are occluded and divided, depending on whether the ovaries will be removed. The round ligament is cut in a similar fashion, and the utero-vesicle peritoneum is incised. Depending on physician preference, the proximal uterine blood supply is occluded and divided laparoscopically. After the utero-vesicle peritoneum is incised, the physician also may choose to laparoscopically incise the posterior cul-de-sac. The physician then proceeds vaginally for the remainder of the case, dissecting the vesico-vaginal septum anteriorly to enter the anterior cul-de-sac, ligating the uterine vessels, removing the uterus and ovaries (if appropriate), and closing the vaginal cuff.
LH, the second approach, is performed initially like the LAVH, except that the entire hysterectomy is performed laparoscopically. The surgeon would choose indications similar to LAVH but would add lack of uterine descent, which would make the vaginal approach impossible. After the infundibular, utero-ovarian, and round ligament are occluded and divided, the bladder is dissected off the uterus anteriorly. The ureter is identified and dissected along its entire course, and then the uterine vessels and uterosacral ligaments are occluded and divided. After the posterior cul-de-sac is incised, the specimen is removed vaginally and the cuff is closed.
LSH is the third approach, being most often promoted for benign indications. The technique begins again as for the LAVH, but proceeds with separating the entire fundus from the cervix after the proximal vessels are divided and the bladder is dissected away from the uterus. A special instrument is used to core out or cauterize the endocervix, and then the uterus is removed through a 12-mm port abdominally by morcellation or transcervically with a special morcellator. This approach eliminates vaginal and abdominal incisions with no need to dissect near the uterine artery or ureter. Proponents of LSH advocate that the operating room and recovery time are decreased, and risk of both infection and ureteral injury are minimized. Concern for future development of cervical cancer, however, remains due to the presence of the cervical stump.
Laparoscopy originally was used in oncology for second-look procedures following surgical and chemical treatment of malignancy. With time, staging, including peritoneal washes with biopsy, partial omentectomy, and pelvic and periaortic lymphadenectomy, was done laparoscopically. Some oncologists believe the laparotomy can then be avoided. Procedures such as laparoscopically assisted radical vaginal hysterectomy also have been developed.
The laparoscopic approach in gynecologic oncology remains very controversial and must be done with the same care (inspecting the entire peritoneal cavity and pelvic structures) as with laparotomy. Until the risk, benefits, and effects on long-term prognosis have been shown to be equal to laparotomy, the laparoscopic approach will remain under close scrutiny.
|RELEVANT ANATOMY AND CONTRAINDICATIONS||¡@|
Relevant Anatomy: Anterior abdominal wall anatomy should receive special attention prior to laparoscopy since many laparoscopic complications result from trocar placement.
As noted above, previous surgery is associated with a greater than 20% risk of adhesions of bowel or omentum to the anterior abdominal wall. For this reason, many laparoscopists adjust their techniques in these patients to minimize risk of bowel injury. Of special concern are incisional scars immediately adjacent to the umbilicus, since bowel adherent underneath the umbilicus may be at risk for injury regardless of the technique used. Although Pfannenstiel and abdominal incisions distant to the umbilicus also may be associated with adhesions, in many laparoscopists' experience, these incisions appear to represent less of a risk than incisions near the umbilicus.
In addition to location, the width and depth of the scar should be evaluated, since a wide or retracted scar may suggest that a postoperative wound infection had occurred. It is common wisdom that postoperative infections may be associated with an increased risk of intra-abdominal adhesion formation, although no data are available to support this observation. If the dome of the bladder is involved in the infectious process, it may cause progression of the bladder dome higher behind the anterior abdominal wall, thus increasing the risk of bladder injury at the time of suprapubic trocar placement.
Abdominal wall thickness
Although abdominal thickness correlates with patient weight, short stature or truncal obesity may increase abdominal wall thickness out of proportion to patient weight. Routine evaluation of the abdominal wall prior to laparoscopy is important since the success of trocar insertion may depend on altering the technique based on abdominal wall thickness.
The umbilicus should be examined for signs of umbilical hernia. Techniques for trocar insertion should be adjusted, and closure of the defect should be considered. In the absence of incarcerated bowel, the skin over the hernia can be carefully incised and the peritoneal cavity entered using an open technique. Closure of a small defect can be performed with interrupted sutures at the completion of the laparoscopic procedure. Larger defects may require the assistance of a surgeon experienced in umbilical hernia repair for ideal cosmetic results.
Contraindications: Determination of absolute
contraindications to laparoscopy remains controversial. For years, previous
abdominal surgery and intestinal obstruction were regarded as contraindications
to laparoscopy because of an increased risk of iatrogenic bowel perforation.
Recent reports, however, suggest that morbidity is lower with the laparoscopic
approach than with laparotomy. In gynecology, the most commonly suggested
contraindication is hemodynamic instability resulting from an unruptured ectopic
pregnancy. Following appropriate fluid resuscitation, however, laparoscopy is a
safe approach. Another traditional contraindication was pregnancy. In the last
few years, several large series have documented the safety of laparoscopy during
pregnancy with the use of an open technique. Finally, disagreement is ongoing as
to whether a known gynecologic malignancy is a contraindication to laparoscopy.
Several case reports and series have suggested that laparoscopy may increase the
risk of intraperitoneal spread of cancer cells.
Although few absolute contraindications exist for laparoscopy, several risk factors are well appreciated.
It is well appreciated that obesity increases the risk of any abdominal surgery. For laparoscopy, increased weight takes on a special significance. Women with a body mass index (BMI) greater than 25 kg/m2 are classified as overweight, and those with a BMI greater than 30 kg/m2 are considered obese. In an average-sized woman of approximately 160 cm (64 in), these cutoff points correspond roughly to weights of 73 kg (160 lb) and 91 kg (200 lb), respectively.
In women who are overweight, and even more so in those who are obese, every aspect of laparoscopy becomes more difficult and potentially more risky. Placement of laparoscopic instruments becomes much more difficult and often requires special techniques. Bleeding from abdominal wall vessels may become more common since these vessels become difficult to locate. Many intra-abdominal procedures become increasingly difficult because of a restricted operative field secondary to retroperitoneal fat deposits in the pelvic sidewalls and increased bowel excursion into the operative field. This second problem probably is related to increased volume of bowel, decreased elevation of a heavier anterior abdominal wall by the pneumoperitoneum, and the inability to place many obese patients in steep Trendelenburg because of ventilation considerations.
Weight loss prior to elective surgery in overweight and obese patients would be ideal. Unfortunately, significant weight loss may take years and, more often than not, is impossible. A more realistic approach is to inform the patient of the increased risk associated with obesity, and limit the extent of advanced laparoscopic procedures that are attempted in obese patients. Although no certain weight exists at which laparoscopy is contraindicated, many surgeons hesitate to perform all but the simplest laparoscopic procedures in patients weighing over 136 kg (300 lb).
Another well described surgical risk factor is age. As the population ages, more women of increased age will have indications for laparoscopy. Older patients are at increased risk of having concomitant disease processes that affect their perioperative morbidity and mortality.
Probably the single most important consideration is age-associated increase in cardiovascular disease. Risk is increased even greater in women who have not taken replacement hormones after menopause. Intraoperative cardiac stress related to anesthesia and the surgery itself may result in sudden cardiac decompensation based on arrhythmia, ischemia, or infarct.
Of special importance is the increased susceptibility of the elderly to hypothermia since the vast majority of patients experience some degree of hypothermia during laparoscopy. In older patients, even mild degrees of hypothermia may increase the risk of cardiac arrhythmia and prolong recovery time.
Previous abdominal surgery
As far as laparoscopic complications are concerned, one of the most important risk factors is a history of previous abdominal surgery. The risk of adhesions of omentum and/or bowel to the anterior abdominal wall after previous abdominal surgery is greater than 20%. Since laparoscopy requires the insertion of sharp instruments into the abdominal cavity, it stands to reason that previous surgery would increase the risk of bowel injury. Thus, strategies to decrease the risk of bowel injury in patients with previous abdominal surgery have been developed.
The most common of these strategies is the use of an open technique for laparoscopic trocar placement, as first advocated by Hasson. Open laparoscopy techniques almost certainly decrease the risk of bowel injury distant to the umbilicus. To avoid bowel injury at the site of entry, modifications of the open technique have utilized blunt entry of the peritoneal cavity with a hemostat to avoid inadvertently grasping and incising the bowel. In patients with previous laparotomy in which the scar is located at the umbilicus, use of an alternative location (usually in the left upper quadrant) has been recommended for trocar insertion to avoid injury of bowel adherent immediately beneath the umbilicus. Since not much is known about the rate of injuring structures in this area (eg, spleen, colon, common iliac vessels), when using a closed insertion technique, it may be prudent to use an open approach in this alternative location for trocar insertion.
Despite the potential for increased risk of bowel injury after previous laparotomy, some laparoscopists advocate the use of a closed periumbilical trocar insertion techniques in all patients, regardless of a history of previous surgery. One justification is that bowel injury is uncommon (approximately 3 per 10,000 procedures) and open laparoscopy does not completely avoid the risk of bowel injury.
Anesthesiologists are trained not only in the art of providing anesthesia, but also to serve as consultants. This may be one of the least utilized assets available to modern surgeons. Prior to surgery, discuss preparation of any patient with significant health problems with an anesthesiologist. In complex cases, these patients should be seen by an anesthesiologist for optimal preanesthesia preparation.
Time since last oral intake
One of the most critical time-dependent aspects of preparation is the degree to which the patient's stomach is empty, since both general anesthesia and increased intra-abdominal pressure may increase risk of regurgitation and resultant aspiration. The appropriate time to wait from the last oral intake until induction of general anesthesia is a much-debated topic. In general, it is recommended that approximately 6 hours be allowed to elapse between the last intake of solid food and the elective induction of anesthesia. In patients with conditions associated with decreased gastric emptying (eg, diabetes-induced autonomic dysfunction) or in the presence of predisposing factors for regurgitation (eg, sliding hiatal hernia, known reflux), a longer period of fasting may be indicated.
Unfortunately, in emergency cases such as ectopic pregnancy or ovarian torsion, general anesthesia may be required despite a period of fasting of less than 6 hours. In these cases, always consult an anesthesiologist. In many cases, steps can be taken to decrease incidence of aspiration pneumonia, including administration of agents to decrease gastric acidity, such as antacids or histamine receptor antagonists, or use of drugs that increase gastric emptying, such as metoclopramide.
Preoperative evaluation should search for evidence of underlying cardiac disease. With a positive history or physical findings suggestive of cardiac disease, preoperative evaluation by both a cardiologist and an anesthesiologist is extremely important. Patients with ischemic heart disease who undergo anesthesia may have decreased cardiac blood return coupled with an increase heart rate that may result in infarction. Laparoscopic-associated metabolic acidosis, respiratory acidosis, and hypothermia may result in arrhythmia in predisposed patients, thus increasing the risk of ischemia even further. There also is an increase of arrhythmia with distention of the abdomen, especially in patients who are spontaneously breathing.
Finally, patients at risk for congestive heart failure should be evaluated carefully prior to laparoscopy since a decrease in cardiac output may be related to decreased venous return and increased peripheral vascular resistance.
Any patient with significant history of pulmonary problems should be evaluated by both a pulmonologist and an anesthesiologist prior to laparoscopy. When given an option, laparoscopy is preferable to laparotomy in these patients. The relatively decreased postoperative pain following laparoscopy may result in less ventilatory compromise than laparotomy and thus fewer problems with atelectasis or pulmonary failure in those with borderline pulmonary function.
Special care should be taken with patients with pulmonary disease during laparoscopy. Hypercarbia and decreased ventilation associated with laparoscopy may be especially deleterious in pulmonary patients with chronic respiratory acidosis. In rare cases, pneumothorax and pneumomediastinum have been described as complications of abdominal insufflation. In patients with compromised pulmonary function, even a small intravasation of carbon dioxide could result in significant pulmonary decompensation.
Primary trocar placement
Numerous techniques exist for creating a pneumoperitoneum and placing a laparoscopic port into the abdomen. Each is purported to offer a unique advantage. Four common approaches are Veress needle insertion followed by a primary trocar insertion, direct trocar insertion, open laparoscopy, and optical trocar placement. Physician experience significantly contributes to the safety of the individual technique. Both reusable and disposable instruments are available. Choice of instrumentation should take into account the condition of the available reusable equipment and cost of the disposable equipment.
Veress needle and primary trocar insertion
When the Veress needle is placed through the umbilicus into the peritoneal cavity, avoidance of both the retroperitoneal vessels and the intestinal tract is of paramount importance. The patient must be in the complete horizontal position (not Trendelenburg) and the patient's body habitus should be carefully assessed . The abdominal wall is elevated by manually grasping the skin and subcutaneous tissue to maximize the distance between the umbilicus and the retroperitoneal vessels. An alternative method for elevation is to place penetrating towel clips at the base of the umbilicus.
In the average-weight person, the lower anterior abdominal wall is grasped and elevated, and the Veress needle is inserted toward the hollow of the sacrum at a 45?angle . In a very thin patient, the vital structures are much closer to the abdominal wall and the margin for error is reduced, with sometimes as little as 4 cm between the skin and large retroperitoneal vessels. In the obese patient (>200 lb), a more vertical approach, approximately 70-80? is required because of the increased thickness of the abdominal wall. Without the vertical insertion, the trocar would not be long enough to penetrate the layers and enter the peritoneal cavity.
Correct placement of the Veress needle may be confirmed by a number of methods, such as the hanging drop test, injection and aspiration of fluid through the Veress needle, or measurement of intra-abdominal pressure with carbon dioxide insufflation. After a pneumoperitoneum has been achieved with a Veress needle, the primary trocar with sleeve (most commonly 5 mm or 10 mm in diameter) is placed at a similar angle to the Veress needle.
Direct trocar insertion
Direct trocar insertion refers to inserting the primary trocar without having previously inserted the Veress needle and insufflating the abdomen with carbon dioxide. The primary trocar is inserted in a manner similar to Veress needle insertion. The sleeve from the trocar is then used to insufflate the abdomen with carbon dioxide. Although several small studies suggest that the safety of this technique is equal to Veress needle, subsequent larger studies report a bowel injury rate of 0.06-0.09%, which is approximately 3 times the accepted rate of 0.03%.
Open laparoscopy involves incising the anterior rectus fascia and bluntly entering the peritoneal cavity with a Kelly or Crile clamp. A blunt-tipped trocar with sleeve is then placed into the peritoneal cavity. For the Hasson technique, sutures used on the fascia hold the sleeve in place and anchor the sleeve to help maintain a pneumoperitoneum. Because this method almost completely avoids the risk of retroperitoneal vessel injury and may decrease the risk of bowel injury, some laparoscopists use this approach exclusively. Many laparoscopists use this method for patients with risk of abdominal adhesions.
Expanding Access Cannulas
A relatively new technique for laparoscopic trocar placement is the use of expanding access cannulas. This technique involves the placement of a Verres needle for insufflation. After the peritoneal cavity is insufflated, the Verres needle is removes and reinserted after it is place into an expandable sleeve. Once the needle and sleeve are placed into the peritoneal cavity, the needle is removed and the sleeve dilated up to a 5- 10 mm diameter to accommodate a laparoscopic lens. Although this technique has been reported in several hundred cases, the relative risk compared to older techniques remains to be established.
Optical trocar technique
A clear trocar has been developed to penetrate the abdominal layers while visualizing the layers with the laparoscope inserted in the trocar (Endopath Optiview trocar, Ethicon Endo-Surgery, Inc, Cincinnati, Ohio). While large studies documenting the relative safety of this approach are not yet available, some laparoscopists use this method because they believe that it may help avoid vessel and intestinal injuries.
Placement of secondary trocars
Secondary trocars are required to perform most gynecologic laparoscopy procedures, with the exception of some diagnostic laparoscopies. After identifying the epigastric vessels by transillumination and intraperitoneal observation, 1-3 secondary trocars are placed, depending on the procedure and the number of trocars required for the operation.
The trocars are placed either in the midline, 3 cm above the pubic symphysis, or laterally, approximately 8 cm from the midline and 8 cm above the pubic symphysis to avoid the inferior epigastric vessels. Lateral trocars should not be placed 5 cm from the midline and approximately 3 cm above the symphysis as some have suggested, since this correlates very closely to the average location of the inferior epigastric artery, which is 5.5 cm from the midline at this level . Insertion of the trocar and removal of the sleeves are performed under direct laparoscopic visualization while observing for signs of hemorrhage. If the trocar is larger than 8 mm, the fascia is closed with suture after removal of the sleeve to reduce risk of hernia.
Expanding Access Cannulas for Secondary Trocar Placement
The relatively new expanding access cannula technique described above was initially developed for placement of secondary laparoscopic trocars. This technique involves the placement of a Verres needle in an expandable sleeve through the abdominal wall at the desired site under direct visualization. Once the needle and sleeve are placed, the needle is removed and the sleeve dilated up to a 10-12 mm diameter to accommodate laparoscopic instruments. Since the risk abdominal wall vessel injury appears to be related to the size of the trocar used, this technique appears to be effective in reducing such injuries.
Monopolar electrosurgery was the first methodology used for laparoscopic coagulation. In the past 20 years, other methodologies have been developed to minimize risk of inadvertent injury to adjacent tissue, particularly the bowel. Bipolar electrosurgery offers a greater margin of safety because damage is limited by thermal spread rather than by electrical current; however, cutting ability is reduced. The laser offers a precise, rapid, and accurate method of thermally destroying the tissue, although hemostatic effects are less and the cost in more. A recent addition to laparoscopic surgery is the Harmonic Scalpel (Ethicon Endo-Surgery, Inc, Cincinnati, Ohio), which uses ultrasonic waves to produce cutting and coagulation. Scissors, hook, and ball accessories are available. Like laser, decreased hemostasis and increase cost must be considered.
Techniques for large vessel occlusion
As laparoscopy has become more prominent in gynecology, techniques have been designed to offer efficient means of tying and cutting large vessels, such as ovarian and uterine vessels. Traditional suturing with intracorporal or extracorporal knot-tying has been used effectively, but for most surgeons is relatively difficult and slow. The first technique developed to assist in occluding large vessels was the pre-tied suture loop (Endoloop, Ethicon Endo-Surgery, Inc, Cincinnati, Ohio). Although simple and quick, these types of loops can loosen in the immediate postoperative period.
More recently, new instruments have become available to aid in the suturing process. In addition, linear stapling devices have been used for occluding vessels during removal of adnexal structures or laparoscopic hysterectomy (Endo GIA II stapler, United States Surgical Corporation, Auto Suture Company Division, Norwalk, Conn). As with all disposable equipment, potential saved time must be balanced against increased cost. Finally, one of the best and least expensive approaches for occluding large vessels is bipolar electrocautery, although care must be taken to avoid damage to adjacent structures secondary to lateral heat spread.
Estrogen replacement therapy
In postmenopausal women, estrogen replacement therapy (ERT) is an excellent preoperative adjuvant from several perspectives. If surgery for pelvic relaxation (such as vaginal vault suspension) or for urinary incontinence (such as laparoscopic Burch procedure) is planned, several months of ERT prior to therapy will significantly increase tissue thickness, resilience, and blood supply. Well estrogenized genitourinary tissue will make the necessary repair much simpler and may reduce risk of operative site infection.
On a more general level, women using ERT are known to have a lower risk of coronary heart disease; therefore, they also may be reasonably expected to have a decreased risk of cardiovascular complications during surgery.
Gonadotropin-releasing hormone agonists
On the opposite end of the spectrum are premenopausal women who may benefit from temporarily decreasing levels of circulating estrogen by the use of a gonadotropin-releasing hormone (GnRH) agonist. The most common situation in which this is helpful is in the presence of large leiomyoma when size alone makes surgery difficult. This is most common when hysteroscopic resection of a large submucosal leiomyoma is to be attempted or when laparoscopically assisted vaginal hysterectomy is planned for a markedly enlarged uterus. In general, uterine volume can be decreased by up to 50% with 2-3 months of administration of a long-acting GnRH agonist. This also may be helpful in some cases of laparoscopic myomectomy.
Prophylactic antibiotics are a well established method of decreasing risk of postoperative infections after either vaginal or abdominal hysterectomy. Although their use has not been studied in a large number of cases of laparoscopically assisted hysterectomy, it makes intuitive sense that prophylactic antibiotics would be beneficial in these patients as well.
Another group of patients who may benefit from prophylactic antibiotics are women undergoing tubal reconstructive surgery for pelvic adhesive disease resulting from previous pelvic infections. Since these patients appear to be at increased risk for postoperative infections after genital surgery, use of an intraoperative broad-spectrum antibiotic given intravenously seems reasonable.
Risk of postoperative thromboembolism appears to be increased by the preoperative use of high-dose oral contraceptives (50 mg of ethinyl estradiol) in women undergoing major gynecologic surgery. Whether contemporary low-dose preparations (35 mg) share this risk has not been established. Also, no proven risk exists for women using oral contraceptives prior to minor surgery in which significant periods of immobilization are unlikely.
Although some authors believe that oral contraceptives should be discontinued 1 month prior to any elective surgery, no study has established that it is unsafe to continue low-dose oral contraceptives up until the time of most laparoscopic procedures. Women undergoing laparoscopically assisted hysterectomy, however, should probably discontinue oral contraceptives 1 month prior to surgery unless the patient decides that risk of inadvertent pregnancy is greater than the small, but uncertain, increased risk of thromboembolism associated with preoperative oral contraceptives.
If significant enterolysis is planned and either endometriosis or pelvic adhesions are known or suspected to be present, preoperative bowel preparation decreases risk of serious postoperative sequelae. Although a multitude of bowel preparations have been described, the most common oral agents used are either magnesium citrate or a polyethylene glycol solution. Unfortunately, a thorough bowel preparation often is uncomfortable for the patient. In high-risk patients, however, preoperative bowel preparation may allow primary closure of an unplanned enterotomy; in the presence of an unprepared colon, a temporary diverting colostomy may be required.
"NPO after midnight" remains a sound approach in the majority of patients undergoing early morning surgery to avoid the risk of aspiration. In patients whose cases are scheduled later, clear liquids up until 6 hours prior to surgery may make the patient more comfortable and also decrease the degree of preoperative dehydration. For emergency procedures, general anesthesia may be required despite a period of fasting of fewer than 6 hours.
Because of the rare but serious risk of sudden and potentially massive blood loss during laparoscopy, establishment of intravenous access prior to starting the case is required. Usually, this is in the form of a functioning intravenous catheter of at least 18 gauge. A balanced salt solution is administered at a moderate rate to assure that the line is functioning and to hydrate the patient prior to administering of regional or general anesthesia.
Traditionally, complete emptying of the urinary bladder with a catheter immediately prior to Veress cannula or trocar placement is performed to minimize the risk of bladder injury. Some laparoscopists advocate having the patient void immediately prior to entering the operating room. This approach may, on occasion, be associated with the discovery of a significant amount of bladder distention because of incomplete emptying or excellent urine output. In-and-out catheterization appears to more consistently result in compete bladder emptying and, when performed aseptically, appears to be associated with minimal risk of iatrogenic urinary tract infection. For procedures of longer duration, consider use of an indwelling catheter to avoid bladder refilling, although this probably increases the risk of infection.
Deep vein thrombosis prophylaxis
When hysterectomy is planned, intraoperative and postoperative use of pneumatic compression stocking with or without low-dose heparin decreases risk of venous thromboembolic complications. These measures also should be considered in any patient whose ability to ambulate may be decreased by conditions other than the planned surgery. After less extensive laparoscopic procedures in healthy patients, risk of thromboembolism appears to be small since most will be fully ambulatory within hours of surgery. For these patients, methods for deep vein thrombosis prophylaxis are not commonly used.
Gynecologic laparoscopy procedures usually are performed in the dorsal lithotomy position to allow vaginal access for uterine manipulation. In the early days of laparoscopy, this was attained by suspending the ankles in lithotomy stirrups also known as candy cane stirrups. Unfortunately, these stirrups offer little leg support, thus putting increased stress on both the knee and hip joints. In addition, they require that patient be in high lithotomy position, in which the thighs severely limit the range of movement of the operator.
Most laparoscopists now use boot stirrups specially designed for laparoscopy. These resemble obstetric stirrups in that they have a foot plate and also support the popliteal fossa. Laparoscopic stirrups, however, are more adjustable than those previously designed for obstetrics. This avoids pressure on the lateral or posterior aspect of the calf and permits easy positional changes from low lithotomy for laparoscopy to high lithotomy for vaginal procedures, such as hysteroscopy or vaginal hysterectomy.
For low lithotomy, legs should be positioned so that the thigh is slightly flexed, no more than 90?from the plane of the abdomen. The thighs should not be hyperextended to avoided nerve injury. For high lithotomy, legs should be positioned so that the angle between the flexed thigh and the abdomen is no less than 45? The buttock should be slightly over the edge of the table, but the sacrum should be completely supported by the table to avoid back strain.
Once the primary trocar is placed, the patient is usually placed in no more than 25?Trendelenburg position to help keep the bowel out of the pelvis. Unfortunately, the degree of tilt possible may be limited by any resulting compromise in ventilation that may occur, especially in obese patients. In patients who are conscious during regional or local anesthesia, discomfort and dyspnea may be limiting factors. As a warning, the use of steep Trendelenburg for prolonged periods has been associated with Erb palsy, especially with the use of shoulder braces.
Shaving of the pubic hair above the symphysis may be required if hair extends to the intended site of ancillary trocar placement, usually 3-4 cm above the symphysis pubis. Standard antiseptic preparation of the abdominal skin and the vagina are followed by placement of specially designed fenestrated laparoscopy drapes. Vaginal instruments are placed for uterine manipulation and then draped to keep the abdominal field separate from the lower vaginal field.
After changing gloves, avoid contamination of both the abdominal field and instruments place into the abdominal cavity. Prior to video laparoscopy, the operator's eye was placed against the laparoscope, making it impossible to keep the operating field sterile. Nevertheless, risk of infection involving the wound or the peritoneal cavity after laparoscopy is extremely low, most likely because of small incisions and decreased opportunity for intra-abdominal contamination. With the advent of video laparoscopy, there is no reason that standard sterile precautions cannot be applied to all laparoscopic procedures.
Type of anesthesia
Over the years, many methods of anesthesia have been employed for laparoscopy, including general anesthesia, regional blocks, and local infiltration. Because of 2 unique aspects of gynecologic laparoscopy, abdominal insufflation and routine use of the Trendelenburg position, general anesthesia is probably the most common technique.
Abdominal insufflation, usually with carbon dioxide at a pressure of 15-20 mm Hg, has significant physiologic effects. Transperitoneal absorption of carbon dioxide results in a relative acidosis that plateaus after about 15 minutes of insufflation. Acidosis can be corrected by increasing ventilation 10-25% and usually has minimal effect on healthy patients. In susceptible patients, however, these changes in acid-base status may increase risk of cardiac arrhythmia. Probably a more significant effect of abdominal insufflation is increased pressure on abdominal structures. As well as being associated with significant discomfort in conscious patients, increased pressure can result in passive regurgitation of gastric contents, even in patients without a history of gastric reflux. While pressure is increased at the gastroesophageal junction, this does not prevent regurgitation.
Increased intra-abdominal pressure also is transmitted to the thorax. Pressure on the diaphragm increases breathing effort in conscious patients. In patients under general anesthesia, decreased excursion of the diaphragm can lead to atelectasis and functional pulmonary shunt, which in turn can result in hypercarbia and a respiratory acidosis, augmenting the acidosis associated with carbon dioxide absorption.
Abdominal insufflation can have direct cardiac effects as well. Pressure on the intra-abdominal venous system can decrease the venous return to the heart. Pressure transmitted to the right atrium decreases preload further. This may be of minimal consequence in healthy patients, but it may lead to cardiac compromise in those with borderline cardiac function.
Another aspect of laparoscopy that can increase upper abdominal pressure is the use of Trendelenburg position to keep the bowel out of the pelvis. The effects of gravity on intra-abdominal contents increases pressure on the stomach and diaphragm, accentuating the problems discussed above.
Because of the discomfort and risks associated with abdominal insufflation, general anesthesia is the most common technique used for laparoscopy. To minimize the risk of aspiration, endotracheal intubation also is recommended.
Local or regional anesthesia should be used only in carefully selected patients. The chance of significant discomfort and the risk of aspiration should be discussed thoroughly with the patient, and only those able to handle some discomfort are appropriate candidates. During laparoscopy, both the discomfort and the risk of aspiration may be decreased by using the least intra-abdominal pressure possible for insufflation (usually <14 mm Hg) and using the least amount of Trendelenburg position necessary to visualize the pelvis. Unfortunately, this limits the ability to perform extensive procedures in many patients. This is especially problematic in obese patients, who often require relatively high intra-abdominal pressures and steep Trendelenburg to obtain adequate visualization of the pelvis. For this reason, use of local or regional anesthesia should be limited to non-obese patients who have a reasonable amount of pain tolerance and who do not require a significant degree of intra-abdominal surgery.
Postoperative details: After any gynecologic laparoscopic procedure, progressive resolution of symptoms during the first postoperative 3-7 days is to be expected. With major procedures, return to completely normal bowel function may take several days. For any procedure, pain may be perceived as slightly worse on the day following the procedure, but should improve after this point. Likewise, the incision should appear healthy and become almost painless within the first week.
Patients should be counseled on the natural postoperative course of events and patients should be instructed to contact their physician if any deviation from this course occurs. A natural tendency may be to reassure a patient who calls that their postoperative discomfort is within the normal range. This should be done with caution, however, since delay of appropriate care often can compound the effects of complications and may be fatal.
Probably the most concerning postoperative symptom is worsening abdominal pain, especially in the presence of distension. Signs of an occult injury of bowel or bladder may take hours or days to develop. If a patient who calls the physician cannot be assured with absolute certainty that she is not experiencing a surgical complication, she should be advised to come in for an evaluation by someone experienced in recognizing postoperative complications.
An unusual cause of abdominal pain is an entrapped incisional hernia that can occur after laparoscopy. Herniation is rare at the site where the laparoscope is placed through the umbilicus. Bowel herniation, however, has been reported to occur when larger trocars (>5 mm) are used in locations lateral to the midline. Apparently, this is not related to herniation through a fascial defect, but rather entrapment of bowel that has herniated through the peritoneum into the preperitoneal space. This appears to be a different process than an incisional hernia that occurs after laparotomy, where a palpable bulge is the most common presenting symptom, and entrapment is uncommon. After laparoscopy, herniation may present as severe abdominal pain accompanied by signs of bowel obstruction. Although incisional hernias always should be considered as a cause of abdominal pain after laparoscopic surgery, they are relatively infrequent. Thus, other intra-abdominal processes also should be considered.
Follow-up care: In the absence of complications, the patient should be able to return to full activity within 72 hours after most gynecologic laparoscopic procedures other than hysterectomy. Since complete healing of fascial defects takes several weeks, the patient should avoid lifting anything heavier than 15 pounds for the first month.
Recovery from laparoscopic hysterectomy can be expected within 2-3 weeks. Again, since healing continues to take place for the first month, heavy lifting should be delayed for 4 weeks. Follow-up office visits in patients without complications are usually scheduled 2-4 weeks after surgery.
In addition to the traditional risks of surgery such as infection and generalized bleeding, laparoscopy is a technique that presents its own unique complications.
Because carbon dioxide is used in laparoscopy to create the pneumoperitoneum, a gas embolization is an uncommon but very serious complication. Embolization usually is caused by inadvertent placement of the Veress needle in a major vessel prior to insufflation of the abdominal cavity with carbon dioxide. Placement in the aorta or one of its major branches allows carbon dioxide to escape into the vessel, which produces temporary arterial occlusion. Usually the carbon dioxide is quickly absorbed from the artery, and no serious results have been reported secondary to arterial embolization. In these cases, arterial bleeding would be the major complication. On the other hand, embolization of carbon dioxide into the venous system may be fatal due to complete occlusion of the pulmonary artery by a large carbon dioxide embolism.
To avoid this complication, the operator must verify intraperitoneal placement of the Veress needle prior to insufflation. If one of the following tests indicates malposition, the needle must be repositioned:
Recognition and treatment of a large venous embolization must be immediate. Clinical signs include decreased end-tidal carbon dioxide, decreased oxygen saturation, a loud mill-wheel murmur, severe hypotension, and possible cardiac arrest. Treatment includes immediately stopping insufflation, removing the needle, placing the patient in the left lateral decubitus position, administering 100% oxygen, and giving cardiac support. The gas embolism may be broken up with external cardiac massage, but definitive treatment is placement of a central line for aspiration of the gas from the right side of the heart and from the pulmonary vasculature.
Retroperitoneal major vessel injury
Laceration of major abdominal blood vessels is one of the least common but most life-threatening complications in laparoscopy. Injuries, which present in approximately 3 per 10,000 laparoscopies, may occur during insertion of the Veress or the primary trocar.
In theory, the aorta and inferior vena cava are avoided if one inserts the Veress or trocar through the umbilicus toward the hollow of the pelvis, since the umbilicus usually lies over the bifurcation of the aorta at L4. However, 25% of the time the bifurcation is above or below L4. Also, the left common iliac vein frequently crosses directly below the umbilicus. The thin patient poses an additional risk since the distance from the umbilicus to the retroperitoneal vessels may be as short as 2-3 cm. In obese patients, the umbilicus may not lie over L4, therefore palpation of the iliac crest, which is lateral to L4, is a better assessment of the position of the bifurcation.
When placing the Veress needle, the patient must be in the horizontal position (not Trendelenburg), and the angle of entry varies depending on patient weight. Open laparoscopy remains an alternative for avoiding retroperitoneal injury. Immediate recognition of the injury is paramount to patient survival. If blood flows from the open Veress needle or if the patient's vital signs rapidly decompensate after Veress or trocar insertion, prompt action must be taken. With a retroperitoneal hemorrhage, the peritoneal cavity may not show signs of bleeding. If major vessel injury is suspected, notify the anesthesiologist in order to place a central line and order blood products, make a midline incision for good exposure, and immediately call a vascular surgeon. Although some surgeons have advocated keeping the Veress needle in place to mark the position of the injury, this approach has never been tested and may actually impede definitive surgery or inadvertently enlarge the vessel injury.
Abdominal wall vessel injury
As laparoscopy has become more sophisticated, the placement of numerous and larger accessory trocars lateral to the rectus muscles has increased the risk of abdominal wall vessel injury. The primary vessels injured are the epigastrics (inferior and superficial) and the superficial circumflex iliac. The inferior epigastric originates from the external iliac and the superficial from the femoral. Damage can lead to abrupt and significant blood loss, producing a hematoma or postoperative hemorrhage.
The first step to avoiding injury is knowing the positions of these vessels. Often, the superficial vessels can be seen by transilluminating the abdominal wall with the laparoscope. The inferior epigastric artery cannot be transilluminated but may be seen intraperitoneally beneath the peritoneum between the insertion of the round ligament at the inguinal canal and the obliterated umbilical artery. Prior to insertion of the lateral trocars, the operator should make an effort to identify and avoid these vessels.
If unable to visualize the vessels, the operator can enhance success for avoiding the vessels by placing the trocars lateral to their usual location, which is 5.5 cm from the midline. Therefore, placing the trocars 8 cm lateral to the midline and 8 cm above the pubic symphysis should help to avoid injury to the epigastrics. Because of anatomic variations, vessel location can vary. Therefore, additional precautions can be taken by using the smallest trocar possible and choosing a conical over a pyramidal tipped trocar.
When an injury occurs, the operator must be prepared to control the bleeding promptly. First, an attempt can be made to coagulate the vessel with electrocautery. If another port is not available to use electrocautery, a Foley catheter can be placed through the trocar and the balloon inflated with saline. Upward traction on the catheter, maintained with a clamp on the abdominal side, will slow the bleeding until more definitive therapy can be carried out. Once a second port is place, electrocautery can be used. If this approach does not result in homeostasis, transabdominal sutures have been advocated. However, this inexact approach has a risk of loosening in the immediate postoperative period. A more secure technique is to enlarge the incision and selectively ligate the epigastric vessels, which lie just below the rectus abdominus muscle adjacent to the peritoneum.
Both the small and large intestine can be injured by laparoscopy, posing a life-threatening situation for the patient if unrecognized. If the patient has had previous abdominal surgeries or a history of abdominal infections, such as PID or a ruptured appendix, risk of injury to bowel adhered to the abdominal wall increases. Frequently, surgeons will choose the open laparoscopy approach for these cases.
Recently, with the introduction of disposable trocars, the relative safety of these instruments has been argued. The disposables have a safety shield, which is designed to extend over the blade and decrease bowel injury with entry of the trocar into the peritoneal cavity. These trocars are extremely sharp and easily penetrate the fascia, which may cause additional injury as the momentum of penetration continues into internal structures.
On the other hand, reusable trocars may not be maintained regularly, and a dull trocar pushed through the fascia with significant force may also abruptly pass through the fascia and cause internal injury. No study has examined the relative safety of disposable and reusable trocars, although one series showed the risk of bowel injury with disposable trocars to be approximately 3 times more than that reported for reusables.
Thermal injury to the bowel also is a risk when using electrocautery, particularly monopolar cautery, which can cause an arc of electricity to the bowel. This injury can cause peritonitis if unrecognized, and it is a life-threatening situation if not promptly treated.
If injury is recognized at the time of surgery, immediate action must be taken to repair the damage. Frequently, however, minor injuries are not seen and manifest themselves 24-48 hours after surgery. Counseling the patient before surgery is of utmost importance. Patients should be aware of symptoms that they must report, such as fever, chills, nausea and vomiting, and abdominal pain. In addition, patient counseling should include the risk of requiring a laparotomy and colostomy to repair injuries.
Injury to the bladder or ureters can occur during trocar placement, use of power instruments, or stapling or suturing devices. The greatest challenge is recognizing that the injury has occurred so that the treatment can be performed in a timely manner.
Draining the bladder with a catheter prior to trocar placement is the first step to preventing bladder injuries. If urine is not seen in the pelvis but an injury is suspected, intravenous indigo carmine can be given and the surgeon should watch for leakage into the peritoneal cavity. If this is negative, but injury is still suspected, a gravity cystogram may be performed. Small retroperitoneal injuries may be treated with a Foley catheter for 7-10 days, but larger or intraperitoneal injures must be repaired through a laparotomy. Suprapubic, retroperitoneal, and transurethral drains may be used depending on the operator and the injury. If bladder injury is unrecognized at time of surgery, the patient may present with diminished urine output, hematuria, or suprapubic pain.
Ureteral injuries can occur with any procedure that uses instruments in the vicinity of the ureters. Thermal injuries from laser or cautery may not be apparent for days after surgery. When a surgeon uses one of the power instruments, the operator must be aware of the position of the ureter, and avoid cautery in close proximity to the ureter. If the ureter is ligated, the patient may present with flank pain secondary to hydronephrosis. If the ureter is transected, the patient may develop a urinoma or ascites and present 1-5 days postoperatively with abdominal pain, fever, or leukocytosis.
Before trocar and sleeves larger than 5 mm were used, incisional hernias were rare. Larger ports, however, have increased the number of incisional hernias, allowing a small amount of bowel to become trapped in the fascia. Therefore, fascial closure is recommended for incisions larger than 5 mm. Umbilical closure is not required unless a very large incision is made, such as with open laparoscopy. The patient is counseled not to perform any heavy lifting or straining for 30 days in order to minimize the risk of umbilical hernia.
|FUTURE AND CONTROVERSIES||¡@|
Laparoscopy continues to evolve as more sophisticated instrumentation allows a greater variety of procedures to be performed. In the past, many of these procedures would have been limited to laparotomy and would have required a prolonged recovery period. The risks and benefits of the procedures in many cases have not been fully evaluated. Some procedures, such as tubal ligation, ectopic pregnancies, and simple lysis of adhesions, appear to be safely and efficiently performed laparoscopically. More complicated procedures, however, still need to be evaluated to determine what is the safest and most efficient procedure.
The laparoscopic approach in gynecologic oncology remains very controversial and must be done with the same care (inspecting the entire peritoneal cavity and pelvic structures) as with laparotomy. Until the risk, benefits, and effects on long-term prognosis have been shown to be equal to laparotomy, the laparoscopic approach will remain under close scrutiny.
|Caption: Picture 1. Anterior abdominal wall anatomy of an obese patient as seen by magnetic resonance imaging. Image courtesy WW Hurd.|
|Picture Type: MRI|
|Caption: Picture 2. Changes in the anterior abdominal wall anatomy with weight for patients in 3 groups: non-obese (BMI <25 kg/m2), overweight (BMI 25-30 kg/m2), and obese (BMI >30 kg/m2). An 11.5-cm Veress needle is superimposed on each view for comparison.|
|Picture Type: Image|
|Caption: Picture 3. Location of deep and superficial vessels of the anterior abdominal wall. Blue circles indicate recommended locations for trocar placement.|
|Picture Type: Image|